n = 51;
A = readmatrix("test3-pol.csv"); Z1pol = A(:,1:n)';
A = readmatrix("test3-her.csv"); Z1her = A(:,1:n)';
A = readmatrix("test3-spl.csv"); Z1spl = A(:,1:n)';
[X,Y] = meshgrid(1:0.02:2,1:0.02:2);
Z1 = 1 - X + Y - X.*Y;
subplot(2, 2, 1);
surf(X,Y,Z1); xlabel('X'); ylabel('Y'); zlabel('Z'); grid on;
subplot(2, 2, 2);
surf(X,Y,Z1pol); xlabel('X'); ylabel('Y'); zlabel('Z'); grid on;
subplot(2, 2, 3);
surf(X,Y,Z1her); xlabel('X'); ylabel('Y'); zlabel('Z'); grid on;
subplot(2, 2, 4);
surf(X,Y,Z1spl); xlabel('X'); ylabel('Y'); zlabel('Z'); grid on;